What is a water blister?

I have a clear blister on my ankle and it is extremely painful. What should I do if its infected?

Answer

Although a water blister can be treated easily, it is important to understand what caused it to occur because they can be symptoms of a more serious problem (i.e., chickenpox or an allergic reaction). A water blister is a small pocket within the upper layers of the skin that fills with a clear, watery substance called serum or plasma. It occurs when the outer layer of a person's skin becomes damaged; so therefore, the fluid is then collected under the injured layer of skin to protect the tissue beneath it and give it an opportunity to heal. It is typically caused by forceful rubbing (friction), such as from wearing tight shoes that constantly rub against the heals or toes. Certain conditions such as chickenpox, herpes and shingles or allergic reaction can give you a water blister. They can also be the result of burning, freezing, chemical exposure or infection. The look of the sore, as well as the individual and cause, can determine the seriousness of a blister. If any sign of infection can be seen, such as severe redness, swelling, soreness or pus, have it checked out by a primary care doctor or a podiatrist - you may need treatment with antibiotics to clear it up.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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